Egg carton with pressure release locking flap



3, 1963 E. M. ALSMAN 3,100,593

EGG CARTON WITH PRESSURE RELEASE LOCKING FLAP Filed Sept. 5, 1961 I I 45 A? EugeneM.H1sman INVENTOR.

tion.

United States Patent 3,100,593 EGG CARTGN WITH PRESSURE RELEASE LOCKING FLAP Eugene M. Alsman, 5104 SE. Long St, Portland, Greg. Filed Sept. 5, 1961, Ser- No. 136,112 1 Claim. (Cl. 229-25) This invention relates to egg cartons, particularly molded pulp egg cartons of the class provided with looking flaps for releasably interlocking the bottom and cover sections.

Although many types of egg cartons provided with locking flaps heretofore have been devised, it has been a problem common to .all of them that the eggs contained in the carton and bearing against the locking flap press it so tightly against the cover that the carton can not be opened without multilation. This is particularly true when the eggs are oversize.

Furthermore, it has been somewhat awkward to open the prior art cartons since two hands are required, one to depress the flap and the other to elevate the cover.

It is the general object of the present invention to provide egg cartons, particularly molded pulp egg cartons, provided with locking flaps which may be locked securely but which may be opened readily without multilation of the carton. It is a further object of the invention to provide egg cartons of the indicated class which may be opened with the thumb of the same hand used to support the canton, thereby leaving the other hand free for other purposes.

The manner in which the foregoing and other objects of the invention are accomplished will be apparent from the accompanying specification and claim considered together with the drawings, wherein:

FIG. 1 is a fragmentary plan view of the presently described egg carton with the cover closed and locked;

FIG. 2 is a view in front elevation of the carton of FIG. 1; and

FIG. 3 is a fragmentary view, partly in section taken along line 33 of FIG. 2, illustrating the carton and particularly illustrating the locking and lock release mechanism of the carton.

Broadly stated, the egg carton of my invention comprises a bottom. section provided with egg cups and with an upstanding locking flap hinged to its front edge. The locking flap is provided with at least one outwardly projecting locking tab. A dished top section is hinged along its back edge to the back edge of the bottom sec- It includes a front panel adapted to overlie the locking flap and provided with laterally spaced, lockingtab-receiving openings, one for each locking tab.

The locking panel also is provided with an opening, preferably a centrally located marginal recess dimensioned to permit the application of digital pressure to the locking flap for releasing the tabs from locking engagement with the cover. This permits unlocking and raising the cover with the same hand used to support the egg carton, without multilation of either the cover or bottom sections thereof.

Considering the foregoing in greater detail and with particular reference to the drawings:

In the drawings there is illustrated a 3 x 4 type molded pulp egg carton which includes a bottom section in which are formed integral egg cups 12 arranged in rows in the usual manner. A flange 14 extends about its periphery.

A reversely bent extension of flange 14 extends along the front end of the carton and forms an upstanding locking flap 16 from which project at least one outwardly projecting locking tab 18. In the illustrated form of,

the invention there are two such tabs, spaced laterally from each other and extending outwardly a distance sufficient to engage and lock, in place a cover section indicated generally at 20.

Cover section 20 is provided with a peripheral flange 22, the lower face of which meets with the upper face of flange 14 on the bottom section. Also, it is hinged to the bottom section by means of a reversely bent, integral hinge along its back edge.

The cover section further includes a front panel 24 in which are formed one or more spaced openings 26 opposite tabs 18 on locking flap 16. These are adapted to receive the tabs in releasable locking engagement.

To permit opening of the carton, particularly when pressure is exerted from the inside against locking flap 16 by the presence of oversize eggs in cups 12, there is provided an opening 28 in a suitable location on front panel 24 of the cover. Preferably opening 28 comprises a centrally located marginal recess dimensioned to receive the thumb of the carton user. The outwardly projecting flange 28 surrounds the opening 28 and forms a continuation of the peripheral flange 22.

Accordingly it is possible for the user to hold the carton in one hand with the thumb opposite opening 28. Pressure of the thumb then may be exerted through the opening against locking flap 16, withdrawing tabs 18 from their respective openings and permitting elevation of the cover for removal of eggs from the carton. This may be done using one hnad only, and without tearing or otherwise mutilating the carton.

The foregoing operation is achieved as follows: If the eggs are small, the flap 16 may he pushed inward by the thumb sufliciently to completely release the tabs 13 from the openings 26. The thumb nail then is pushed upward against the outwardly projecting flange 28 which surrounds the opening 28, causing the cover 20 to be flipped to open position. On the other hand, if the eggs are so large as to prevent the flap 1 6 from being pushed inward sufliciently to completely release the tabs 18 from the openings 26, thethumb nail is caused to push upward on the outwardly projecting flange 28 which surrounds the opening 28. The lower edges of the openings 26 thus slide along the surfaces 18' of the tabs 18, which surfaces project angularly outward away from the flange 22, thereby cumming the front panel 24 outward and upward over the tabs 18 and releasing the cover section.

It is to be understood that the form of my invention herein shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention or the scope of the subjoined claim.

Having thus described my invention, I claim:

An egg carton comprising a bottom section provided with egg cups and with an upstanding locking flap hinged to its front edge, the locking flap bieng provided with at least one outwardly projecting locking tab, a dished top section hinged along its back edge to the back edge of the bottom section for opening and closing on the bottom section, the top section including a front panel adapted to overlie the locking flap in adjacent relation in the closed position of the top section, the front panel being provided with one tab-receiving opening for each locking tab, and with a digit opening extending inward from the edge thereof and dimensioned to expose the locking flap to the external application of digital pressure for rotating the locking flap away from the overlying front panel when in closed position for releasing the tabs from locking engagement with the tab-receiving opening in the front panel of the cover, the bottom section and cover section each having a flange extending outward from the peripheral edge thereof, the flange on the cover section extending around the edge of the digit opening for engagement by a digit for moving the cover section to open position, the locking tab having a surface facing the flanged edge of the cover section when in closed position, which surface extends 'angularly outward away from said flanged edge of the cover section, whereby digital pressure applied under the flange around the digit opening in the opening direction of the cover section effects Withdrawal of the locking tab from its tab-receiving opening.

References Cited in the file of this patent UNITED STATES PATENTS 2,579,346 Theander Dec. 18, 1951 2,974,847 Hurn et al Mar. 14, 1961 FOREIGN PATENTS 1,239,647 France July 18, 1960 

